The major goals of this Core Facility, which was renovated by the University of Arizona specifically for this Program Project Grant are to synthesize, purify and analyze 200 mg to 5 g quantities of biologically active peptides that are needed for extensive biochemcal, pharmacological, biophysical and biological studies, and for toxicological studies which are part of this Program Project Grant. Of importance will be the development of proper synthetic, purificaiton and analytical methodologies for preparation of peptides for the extensive biological and toxicology studies needed if one is eventially apply for clinical trials with the FDA. The Specific Aims of the Core Facility are: 1) To prepare 1g to 10g quantities of the following ligands: a) c[D-Pen2,D-Pen5] enkephalin (DPDPE); b) biphalin; c) c[Phe(pCl)4]DPDPE; d) deltorphin II; e) [Cys4]deltorphin and perhaps other potent an selective compounds. For a) and b) to also establish a "gold standard" for preclinical studies and clinical trials. 2) to establish and develop all necessary analytical methods, purification protocol, and synthetic methods that are needed for preparing ligands for the various needs of all investigators in the Program Project and that are acceptable to the FDA. 3) To prepare by asymmertic synthesis and other synthetic methods the necessary amino acids needed for the preparation of ligands for the Program Project. 4) to prepare up to gram quantities of highly potent peptides, peptidomimetics, peptide conjugates that are needed for further biological of biophysical studies. These include [Phe(pCl)4.4]biphalin, Tyr-D-Pen-Gly-Phe-Cys-Ser(O-Gluc)-Gly, and lipid-deltorphin conjugates. 5) To prepare other peptides or peptidomimetic ligands that are discovered, and that are needed by investigators in the Program Project Grant for further biological or biophysical studies.